1. Field of the Invention
The invention relates to a hinge assembly, more particularly to a hinge assembly capable of damping door movement of a door panel or the like relative to a frame.
2. Description of the Related Art
Referring to FIGS. 1 to 3, a conventional hinge assembly 1 is shown to be mounted between a door frame 21 and a door panel 22 to permit pivotal movement of the door panel 22 between open and closed positions relative to the door frame 21. The hinge assembly 1 includes: a securing seat 11 mounted to an inner side of the door frame 21; a housing 12 mounted in a recess formed in an inner side of the door panel 22; a hinge member 13 having a first pivot end 131 mounted pivotally to the securing seat 11 via a first pivot pin 132, and a second pivot end 130 mounted pivotally to the housing 12 via a second pivot pin 133; a positioning member 14 having a first pivot end portion 141 mounted pivotally to the securing seat 11 via a third pivot pin 143 and disposed closer to the inner side of the door frame 21 than the first pivot pin 132, a second pivot end portion 140 mounted pivotally to the housing 12 via a fourth pivot pin 144, and a tab 142 projecting transversely from the first pivot end portion 141; and a spring 15 sleeved on the first pivot pin 132. The spring 15 has two distal ends abutting against an inner wall surface of the securing seat 11, and a protruding intermediate portion abutting against the tab 142. The second and fourth pivot pins 133, 144 are integrally formed as a U-shaped pin. The second pivot pin 133 is disposed closer to a closed inner end of the housing 12 than the fourth pivot pin 144. When the door panel 22 is in the closed position (FIG. 3), the fourth pivot pin 144 is located inwardly of an imaginary line (L) passing through the second and third pivot pins 133, 143 with respect to the first pivot pin 132, and the first pivot pin 132 is located within the housing 12.
When a force is exerted to push the door panel 22 from the closed position (FIG. 3) to the open position (FIG. 2), the hinge member 13 and the positioning member 14 turn pivotally and angularly about the respective pivot pins 132, 133, 143, 144 against the biasing action of the spring 15, with the tab 142 abutting against and depressing the intermediate portion of the spring 15. When the fourth pivot pin 144 is located between the first and second pivot pins 132, 133 and outwardly of the line (L), the door panel 22 is maintained in the open position against the biasing force of the spring 15, and a restoring force is stored in the spring 15. Thereafter, when a force is exerted to push the door panel 22 to move from the open position back to the closed position, the positioning member 14, as well as the hinge member 13, turns pivotally in a reverse direction. When the fourth pivot pin 144 is located inwardly of the line (L), the intermediate portion of the spring 15 is relieved of the pressure exerted by the tab 142 on the first pivot end portion 141 of the positioning member 14, and resumes its original position with a spring force that restores the positioning member 14, and hence the hinge member 13, to their original positions, thereby bringing the door panel 12 to the closed position.
The aforesaid conventional hinge assembly, however, suffers from the setback that the release of the restoring force in the spring 15 is abrupt so that the closing movement of the door panel 22 is likely to generate a banging sound, and may even hit the person using the door.
Therefore, the main object of the present invention is to provide a hinge assembly for interconnecting a door panel and a door frame, which can damp closing movement of the door panel relative to the door frame.
Accordingly, a hinge assembly of the present invention is adapted to interconnect a door frame and a door panel. The door panel has a proximate end disposed proximate to the door frame, and a recess formed in the proximate end. The hinge assembly includes:
a securing seat including a hollow seat body extending in a first direction, the seat body including vertically spaced-apart upper and lower side walls adapted to be connected to the door frame, an outer side wall interconnecting the upper and lower side walls and opposite to the door frame in a second direction that is transverse to the first direction, and a rear side wall, thereby confining a receiving space with an open front end and a closed rear end opposite to the open front end in the first direction;
a housing adapted to be disposed in the recess and having proximate and distal end walls opposite to each other in a third direction, and an open outer end and closed inner end opposite to each other in a fourth direction transverse to the third direction;
a hinge member having a first pivot end connected pivotally to the seat body at a first pivot point, and a second pivot end connected pivotally to the housing at a second pivot point;
a positioning member disposed between the seat body and the housing, the positioning member having a first pivot end portion pivoted to the seat body at a third pivot point, and a second pivot end portion pivoted to the housing at a fourth pivot point;
the first pivot point being disposed outwardly of the receiving space and proximate to the outer side wall of the seat body, the third pivot point being disposed in the receiving space and distal from the outer side wall of the seat body;
the second pivot end of the hinge memeber and the second pivot end portion of the positioning member extending into the housing via the open outer end, the second pivot point being disposed closer to the inner end of the housing than the fourth pivot point, the fourth pivot point being disposed closer to the proximate end wall of the housing than the second pivot point; and
a damping unit including a fluid cylinder disposed in the receiving space and having one end connected to the seat body, and a piston rod extending through the other end of the fluid cylinder, the piston rod having an actuating end mounted on the first pivot end portion of the positioning member at a fifth pivot point offset from the third pivot point such that, when the door panel is rotated relative to the door frame from a closed position to an open position, the piston rod is retracted into the fluid cylinder to damp opening movement of the door panel, and such that, when the door panel is rotated from the open position to the closed position, the piston rod is extended from the fluid cylinder to damp closing movement of the door panel.